BERKELEY — On Tuesday, July 27, the PBS POV documentary series will air “Presumed Guilty”,a riveting examination of the Mexican judicial system created by UC Berkeley Goldman School of Public Policy doctoral candidates Roberto Hernández and Layda Negrete. In the Bay Area, the film will air at 10:30 p.m. on KQED.

Hernández and Negrete, both attorneys, document their struggle to free a wrongfully imprisoned man and to expose a Mexican criminal justice system that imprisons thousands of other innocent people like him.

PBS says this about the documentary: “Imagine being picked up off the street, told you have committed a murder you know nothing about and then finding yourself sentenced to 20 years in jail. In December 2005 this happened to Tono Zuniga in Mexico Cityand, like thousands of other innocent people, he was wrongfully imprisoned. ‘Presumed Guilty’ is the story of two young lawyers and their struggle to free Zuniga. With no background in film, Roberto Hernández and Layda Negrete set about recording the injustices they were witnessing, enlisting acclaimed director Geoffrey Smith (“The English Surgeon”) to tell this dramatic story.”